The present invention relates to novel compounds, to herbicidal compositions containing the compounds, to the utility of the compounds for the control of unwanted vegetation, to a process for the manufacture of the compounds, and to certain novel intermediates used in their manufacture.
The control of unwanted vegetation by means of chemical agents, i.e., herbicides, is an important aspect of modern agriculture and land management. While many chemicals that are useful in unwanted vegetation control are known, new compounds that are more effective generally or for specific plant species, are less damaging to desirable vegetation, are safer to man or the environment, are less expensive to use, or have other advantageous attributes are desirable.
It is known that certain 1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamides possess herbicidal activity (European Application No. 0142152, published May 22, 1985). The compounds are effective against unwanted vegetation when applied to the vegetation or its locus either pre-emergence or post-emergence. Various methods for their preparation and the preparation of the requisite intermediates are also reported. 1,2,4-Triazolo[1,5-a]1,3,5-triazine-2-sulfonamides possessing herbicidal properties are also known (U.S. Pat. No. 4,605,433).